Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Jaddi Lifestrider

When Jaddi Lifestrider enters the battlefield, you may tap any number of untapped creatures you control. You gain 2 life for each creature tapped this way.

Lathiel, the Bounteous Dawn

Lifelink
At the beginning of each end step, if you gained life this turn, distribute up to that many +1/+1 counters among any number of other target creatures.

Voracious Wurm

Voracious Wurm enters the battlefield with X +1/+1 counters on it, where X is the amount of life you've gained this turn.

Accomplished Alchemist

{T}: Add one mana of any color.
{T}: Add X mana of any one color, where X is the amount of life you gained this turn.

Ageless Entity

Whenever you gain life, put that many +1/+1 counters on Ageless Entity.

Stream of Life

Trelasarra, Moon Dancer

Whenever you gain life, put a +1/+1 counter on Trelasarra, Moon Dancer and scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Ivory Tower

At the beginning of your upkeep, you gain X life, where X is the number of cards in your hand minus 4.

Honor Troll

Vigilance
If you would gain life, you gain that much life plus 1 instead.
Honor Troll gets +2/+1 as long as you have 25 or more life.

Sproutback Trudge

This spell costs {X} less to cast, where X is the amount of life you gained this turn.
Trample
At the beginning of your end step, if you gained life this turn, you may cast Sproutback Trudge from your graveyard.

Fruit of the First Tree

Enchant creature
When enchanted creature dies, you gain X life and draw X cards, where X is its toughness.

Fog of War

You gain 1 life for each creature on the battlefield. Prevent all combat damage that would be dealt this turn by creatures with power 3 or less.

Felidar Sovereign

Vigilance, lifelink
At the beginning of your upkeep, if you have 40 or more life, you win the game.

Plains

Ezzaroot Channeler

Reach
Creature spells you cast cost {X} less to cast, where X is the amount of life you gained this turn.
{T}: You gain 2 life.

Chalice of Death

Chalice of Life

{T}: You gain 1 life. Then if you have at least 10 life more than your starting life total, transform Chalice of Life.

Chalice of Life // Chalice of Death

Wild Dogs

At the beginning of your upkeep, if a player has more life than each other player, the player with the most life gains control of Wild Dogs.
Cycling {2} ({2}, Discard this card: Draw a card.)